Cruise, the self-driving car subsidiary of GM that also has backing from SoftBank Vision Fund, Honda and T. Rowe Price & Associates, has been issued a permit from California regulators that will allow it to test driverless vehicles on public roads in San Francisco.

The California DMV, the agency that regulates autonomous vehicle testing in the state, said the permit allows the company to test five autonomous vehicles without a driver behind the wheel on specified streets within San Francisco. Cruise has had a permit to test autonomous vehicles with safety drivers behind the wheel since 2015.

Ammann described the issuance of the driverless permit as a low-key but milestone moment for the company, which has been working on autonomous vehicle technology for six years.

“The drama of this might be hard to appreciate. All anyone will see is a car, silently driving by itself through the city. Not speeding. Not crashing. Just quietly cruising,” he wrote. “But even without a literal launch into the sky, this is our moonshot. And the chaotic, gritty streets of SF are our launchpad. This is where years of blood, sweat and tears have been poured out by everyone on the Cruise mission. And it’s where over two million miles of city testing will truly hit the road for the first time: An electric car, driving by itself, navigating one of the most difficult driving cities in the world.”

The driverless permit, which means no humans will be behind the wheel, comes with certain restrictions. The Cruise vehicles are designed to operate on roads with posted speed limits not exceeding 30 miles per hour, during all times of the day and night, but will not test during heavy fog or heavy rain, the DMV said. Any company applying for a driverless permit must provide evidence of insurance or a bond equal to $5 million, verify vehicles are capable of operating without a driver, meet federal Motor Vehicle Safety Standards or have an exemption from the National Highway Traffic Safety Administration, and be an SAE Level 4 or 5 vehicle.

Cruise is the fifth company to be issued the driverless permit in California. Waymo, AutoX, Nuro and Zoox also have driverless permits. Currently, 60 companies have an active permit to test autonomous vehicles with a safety driver, according to the DMV.